#!/usr/bin/perl

use strict;
use warnings;

while (<DATA>) {
    my $line = $_;
    my $not = '';
    if ($line !~ /word1(([,\s]+\w+)?){1,4}\s+word2/) {
        $not = 'NOT ';
    }
    print "$line \tdoes $not match the regexp.\n";
}


__DATA__
word1 is made of word2
word1, which is an important thing because of its use and stuff, is made of word2.

##</code><code>##

word1 is made of word2
        does  match the regexp.
word1, which is an important thing because of its use and stuff, is made of word2.
        does NOT  match the regexp.